Lady Bird Reservoir 2019 Fisheries Management Survey Report - Texas Parks and Wildlife
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Lady Bird Reservoir
2019 Fisheries Management Survey Report
PERFORMANCE REPORT
As Required by
FEDERAL AID IN SPORT FISH RESTORATION ACT
TEXAS
FEDERAL AID PROJECT F-221-M-4
INLAND FISHERIES DIVISION MONITORING AND MANAGEMENT PROGRAM
Prepared by:
Mukhtar Farooqi, Assistant District Management Supervisor
and
Patrick Ireland, District Management Supervisor
Inland Fisheries Division
San Marcos/Austin District, San Marcos, Texas
Carter Smith
Executive Director
Craig Bonds
Director, Inland Fisheries
July 31, 2020
i
Contents
Contents ......................................................................................................................................................... i
Survey and Management Summary ............................................................................................................. 1
Introduction.................................................................................................................................................... 2
Reservoir Description ................................................................................................................................ 2
Angler Access ............................................................................................................................................ 2
Management History ................................................................................................................................. 2
Methods......................................................................................................................................................... 5
Results and Discussion ................................................................................................................................. 5
Fisheries Management Plan for Lady Bird Reservoir, Texas ....................................................................... 8
Objective-Based Sampling Plan and Schedule (2020–2024) ..................................................................... 10
Literature Cited ............................................................................................................................................ 12
Tables and Figures ..................................................................................................................................... 13
Reservoir Characteristics ....................................................................................................................... 13
Boat Ramp Characteristics . ................................................................................................................... 13
Harvest Regulations . .............................................................................................................................. 14
Stocking History. ...................................................................................................................................... 15
Objective-Based Sampling plan for 2019–2020. ..................................................................................... 17
Structural Habitat Survey......................................................................................................................... 18
Aquatic Vegetation Survey . .................................................................................................................... 18
Gizzard Shad ........................................................................................................................................... 19
Redbreast Sunfish ................................................................................................................................... 20
Bluegill ..................................................................................................................................................... 21
Redear Sunfish ........................................................................................................................................ 22
Common Carp ......................................................................................................................................... 23
Largemouth Bass .................................................................................................................................... 24
Proposed Sampling Schedule ................................................................................................................. 26
APPENDIX A – Map of sampling locations ................................................................................................. 27
APPENDIX B – Map of structural habitat .................................................................................................... 28
APPENDIX C – Map of vegetation survey .................................................................................................. 29
APPENDIX D – Catch rate of all targeted species from all gears............................................................... 30
1
Survey and Management Summary
Fish populations in Lady Bird Reservoir were surveyed in 2017 and 2019 using electrofishing. Historical
data are presented with the 2017 and 2019 data for comparison. Aquatic vegetation was monitored by
annual surveys. This report summarizes results of the surveys and contains a fisheries management plan
for the reservoir based on those findings.
• Reservoir Description: Lady Bird Reservoir is a stable-level, 469-acre impoundment of the
Colorado River located in the city of Austin, Travis County, Texas. Prior to 2007 the reservoir
was named Town Lake. The reservoir runs through the mid-section of the city and was
constructed in 1960 for purposes of flood control, municipal and industrial water supply, and
recreation. The reservoir is owned and operated by the City of Austin. The reservoir lies
within the Edwards Plateau ecological area and has a shoreline length of 18.3 miles and a
drainage area of approximately 38,240 square miles. Some of the adjacent land has been
developed into city parks. Other shoreline areas have been developed by private businesses.
• Management History: Important sportfish included Largemouth Bass and Common Carp.
Largemouth Bass were managed under a 14-inch minimum length limit until September 1,
2000 when a 14- to 21-inch slot length limit was initiated. Florida Largemouth Bass were
initially stocked in 1998 to improve Largemouth Bass growth potential.
Lady Bird Reservoir is a popular destination for trophy Common Carp anglers from around
the country and from abroad because of the opportunity to catch 30- to 40-plus-pound carp.
The reservoir holds the rod and reel state record for Common Carp at 43.75 pounds. In 2009,
a harvest restriction was implemented to protect trophy-sized Common Carp; only one carp
33 inches or greater may be retained per day.
Lady Bird Reservoir holds the state record (rod and reel) for nine species of fish, which is
more than any other public waterbody in Texas.
Low vegetative coverage has been characteristic of Lady Bird Reservoir.
• Fish Community
Prey species: Redbreast Sunfish, Bluegill, Gizzard Shad and Redear Sunfish were the
predominant prey species. Catch rate for Redbreast Sunfish had increased since the
previous survey, but Bluegill and Redear Sunfish had declined. Gizzard Shad abundance
has declined since 2015.
Common Carp: Historical data indicates that Lady Bird Reservoir had a low-density
carp population dominated by larger individuals and this is partially reflected in more
recent data.
Largemouth Bass: Largemouth Bass abundance had declined since the previous two
surveys, but was still moderate in 2019. The fish were in good condition, and displayed
adequate growth. Population size structure was good.
Management Strategies: Based on current information, the reservoir should continue to be managed
with existing regulations. Biennial aquatic vegetation surveys should be conducted to monitor for the
potential establishment of the non-native species hydrilla, and for changes to the aquatic vegetation
community that could be attributed to the emigration of Grass Carp from upstream Austin Reservoir.
Continue collection of information on Grass Carp and Common Carp populations in collaboration with the
Carp Anglers Group (CAG). Conduct a standard electrofishing survey in 2023. Access and habitat
surveys will be conducted in 2023. Schedule a creel survey as time permits.
2
Introduction
This document is a summary of fisheries data collected from Lady Bird Reservoir in 2017 and 2019. The
purpose of the document is to provide fisheries information and make management recommendations to
protect and improve the sport fishery. While information on other fishes was collected, this report deals
primarily with major sport fishes and important prey species. Historical data are presented with the 2017
and 2019 data for comparison.
Reservoir Description
Lady Bird Reservoir is a stable-level, 469-acre impoundment of the Colorado River located in the city of
Austin, Travis County, Texas. Conservation level is 428 feet above mean sea level. The reservoir runs
through the mid-section of the city and was constructed in 1960 for purposes of flood control, municipal
and industrial water supply, and recreation. The reservoir is owned and operated by the City of Austin
(COA). The reservoir lies within the Edwards Plateau ecological area and has a shoreline length of 18.3
miles and a drainage area of approximately 38,240 square miles. The reservoir is eutrophic with a mean
TSI chl-a of 55.48, and a 10-year change of +5.9 (Texas Commission on Environmental Quality 2020).
Barton Springs Creek in Austin is a small tributary of Lady Bird Reservoir and was the site of the first state
fish hatchery in Texas. The facility was mandated by the Legislature and built for the propagation of
Common Carp in 1881 (Thompson 1943).
Some of the land bordering the reservoir has been developed into city parks. Other shoreline areas have
been developed by private businesses. The 10-mile Ann and Roy Butler Hike-and-Bike Trail, which
follows the shoreline of the reservoir, is Austin’s most recognized and popular recreational area with more
than 1.5 million visits a year. The boardwalk portion of the trail was built in June 2014 allowing trail users
to easily and safely circumnavigate the reservoir. The $28 million project features 13,000 LED lights,
seven viewing areas, ADA accessible pier, and a new trailhead restroom along the 7,250 feet boardwalk.
Habitat at time of sampling consisted primarily of natural shoreline (86.7%). Vegetation (primarily
waterwillow and bulrush) covered approximately 4% of reservoir surface area. Other descriptive
characteristics for Lady Bird Reservoir are in Table 1.
Angler Access
Boat access was adequate and consisted of three public boat ramps and a designated canoe/kayak
access ramp in the COA Red Bud Park. The use of gasoline-powered motors was prohibited by city
ordinance; however, the use of electric trolling motors was permitted.
Bank fishing access was good. The boardwalk is open from 5 am to midnight each day. Fishing is allowed
on the rest areas, but not along the main trail of the boardwalk. In 2017, a wheelchair accessible fishing
pier was built and incorporated into the boardwalk using funds raised by the CORE Health Foundation.
Additional boat ramp characteristics are in Table 2.
Management History
Previous management strategies and actions: Management strategies and actions from the previous
survey report (Farooqi and De Jesus 2016) included:
1. Continue annual aquatic vegetation surveys.
Action: Aquatic vegetation surveys were conducted annually from 2016 to 2019.
2. Continue collecting catch rate information on Grass Carp during electrofishing surveys and
from bycatch at the Austin Team Championship (ATC) Common Carp tournament.
Action: One Grass Carp was observed during the 2019 electrofishing survey. Grass
Carp were captured at the ATC tournament; however, anglers have been reluctant to
formally report them as they are not required for the tournament.3
3. Conduct an additional electrofishing survey to monitor Grass Carp and Largemouth Bass
populations in response to vegetation dynamics.
Action: An additional electrofishing survey was conducted in 2017.
4. Continue to work with the COA to provide input relative to safeguarding angling access on
the boardwalk.
Action: Communication with the COA was maintained and there was no further
initiatives limiting angler access to the boardwalk.
5. Continue collecting length-frequency information on Common Carp during standard
electrofishing surveys and continue working with the Carp Anglers Group to access catch
data at carp tournaments.
Action: Four Common Carp were caught during the standard electrofishing survey in
2019. Due to unknown factors, tournament catch data for the Austin Team Championship
(ATC) was not made available from 2017 to 2019 and there was no tournament in 2020.
6. Cooperate with the COA to educate the public about invasive species through the use of print
media, social media, and public engagements.
Action: Outreach efforts regarding invasive species included social media, print media,
TV interviews, public presentations, and one-on-one interactions with constituents.
Harvest regulation history: Sportfish in Lady Bird Reservoir are currently managed with statewide
regulations with the exception of Largemouth Bass and Common Carp (Table 3).
From 1985 to 1999, Largemouth Bass were managed with a 14-inch minimum length limit. A 14- to 21-
inch slot length limit was implemented in 2000 to: increase abundance of bass greater than 14 inches in
length; increase angler catches of bass greater than 14 inches in length; and, re-direct harvest at
individuals less than 14 inches in length.
In 2009, a harvest restriction was implemented to protect trophy Common Carp; only one carp 33 inches
or greater may be retained per day. There is no daily bag limit for carp less than 33 inches in length. The
33-inch maximum length limit was based on Gablehouse’s (1984) designation for trophy carp.
Stocking history: Florida Largemouth Bass were stocked in 1998 and 2016 to improve the growth
potential for Largemouth Bass. Largemouth Bass ShareLunker offspring were stocked in 2014. These
fingerlings were derived from a 13-pound Largemouth Bass caught by an angler in Lady Bird Reservoir
and submitted to the selective breeding program in 2014. Surplus Channel Catfish fry were stocked in
2018. The complete stocking history is in Table 4.
Vegetation/habitat management history: Prior to 2012, vegetative cover had been low in Lady Bird
Reservoir (Magnelia and Bonds 2004, Magnelia and De Jesus 2008). Vegetation was restricted to
shallow sediment flats adjacent to creek mouths, shoreline, or directly in creeks like Barton Springs
Creek.
In 2013, dense growths of fanwort (Cabomba caroliniana) traversed the width of Lady Bird Reservoir at
the confluence of Barton Springs Creek. Growth was less extensive in 2014 and 2015.
Austin Reservoir (directly upstream) had dense stands of the exotic plant hydrilla (Hydrilla verticillata;
Magnelia and Bonds 2004) and the possible establishment of this aquatic plant in Lady Bird Reservoir
was of concern, necessitating the need for annual aquatic vegetation monitoring. Floating hydrilla has
often been observed in Lady Bird Reservoir, but has never become established (Magnelia and De Jesus
2008). This has not been an issue since September 2013 when hydrilla abundance declined to zero in
Austin Reservoir.4 Eurasian watermilfoil (Myriophyllum spicatum) has been the dominant non-native species, but abundance has declined since 2012 (8.8 acres). Giant cane (Arundinaria gigantean) was noted during the 2011, 2012, and 2015 surveys and is being managed by COA. Efforts have been taken by COA to establish native aquatic vegetation species via plantings throughout the reservoir. Water Transfer: There are no inter-basin water diversion structures at Lady Bird Reservoir. The reservoir is the last in the chain of “Highland Lakes” on the Colorado River, receiving water directly from Austin Reservoir and discharging directly into the Colorado River.
5
Methods
Surveys were conducted to achieve survey and sampling objectives in accordance with the objective-
based sampling (OBS) plan for Lady Bird Reservoir (TPWD unpublished). Primary components of the
OBS plan are listed in Table 5. All survey sites were randomly selected, and all surveys were conducted
according to the Fishery Assessment Procedures (TPWD, Inland Fisheries Division, unpublished manual
revised 2017).
Electrofishing – Largemouth Bass, sunfishes, Gizzard Shad, and Threadfin Shad were collected by
electrofishing (1 hour at 12, 5-min stations; Appendix A). Catch per unit effort (CPUE) for electrofishing
was recorded as the number of fish caught per hour (fish/h) of actual electrofishing. Ages for Largemouth
Bass were to be determined by a category-2 evaluation requiring otoliths from 13 randomly selected fish
ranging in size from 13.0 to 14.9 inches. (TPWD, Inland Fisheries Division, unpublished manual revised
2017). However, only six fish were available in that size range.
Statistics – Sampling statistics (CPUE for various length categories), structural indices [Proportional Size
Distribution (PSD), terminology modified by Guy et al. 2007], and condition indices [relative weight (Wr)]
were calculated for target fishes according to Anderson and Neumann (1996). Index of vulnerability (IOV)
was calculated for Gizzard Shad (DiCenzo et al. 1996). Standard error (SE) was calculated for structural
indices and IOV. Relative standard error (RSE = 100 X SE of the estimate/estimate) was calculated for all
CPUE and creel statistics.
Habitat – A structural habitat and vegetation survey was conducted in 2019. Habitat was assessed with
the digital shapefile method (TPWD, Inland Fisheries Division, unpublished manual revised 2017).
Results and Discussion
Habitat: In 2019, littoral zone structural habitat consisted primarily of natural shoreline (86.7%; Table 6;
Appendix B). Total coverage estimate of all plant species in 2019 was 0.8% (4.0 acres). From 2016 to
2018 it was 0.6% (2.9 acres), 0.2% (1.0 acre), and 1.7% (8.0 acres) respectively (Table 7 and Appendix
C). By comparison, total coverage ranged from 18.6% (82.7 acres) to 36.0% (162.5 acres) during the
period 2012 to 2015 (Farooqi and De Jesus 2016). During the same period, the overall increase in
vegetative cover was largely due to the expansion of fanwort which ranged from 17.0% (78.4 acres) to
33.9% (159.0 acres). Drought conditions that prevailed from 2011 to 2014 most likely created an
environment in which fanwort could flourish. Since 2016, total aquatic vegetation coverage in this
reservoir has significantly declined falling well short of that considered optimum for productive fisheries
(Dibble et al. 1996, Durocher et al. 1984). The decline of fanwort was mainly due to scouring during flood
events (Brent Bellinger pers. com.) In fact, fanwort was not recorded in 2016, 2017, and 2019.
Eurasian watermilfoil has steadily declined since 2012 (8.8 acres, 0.5 %) and has been absent since
2015 (Farooqi and De Jesus 2016). Hydrilla has never been established in Lady Bird Lake.
Prey species: Redbreast Sunfish, Bluegill, Gizzard Shad, and Redear Sunfish were the predominant
prey species in 2019 (Appendix D). Although less abundant, other sunfish and Threadfin Shad provided
additional forage.
Total CPUE of Gizzard Shad in 2019 (50.0/h) was similar to that obtained in 2017 (47.23/h) and less than
in 2015 (193.0/h; Figure 1). The IOV for Gizzard Shad was 32, indicating that 32% of the population (≤ 8
inches) were vulnerable to existing predators. The IOV had improved since the 2017 survey (IOV = 2), but
was lower than in 2015 (IOV = 46). Threadfin Shad were collected at a rate of 2.0/h in 2019, whereas
46.2/h and 68.6/h were caught in 2017 and 2015 respectively.6 Redbreast Sunfish were the most abundant prey species caught in 2019. Total CPUE of Redbreast Sunfish in 2019 (217.0/h) was higher than in 2017 (171.1/h) and in 2015 (185.0/h). Overall, good catch rates and good population structure have been maintained in this reservoir for the last three surveys. Larger fish (up to 8 inches in length) continued to be present (PSD-P = 2), providing some good fishing opportunities for panfish anglers (Figure 2). Bluegill catch rate had significantly declined compared to the previous two surveys. In 2019, total CPUE of Bluegill was 58.0/h, which was considerably less than in 2017 (269.5/h) and 2015 (253.0/h). The population consisted mainly of smaller fish but, there was some opportunity to harvest fish up to 6 inches in length. Catch rates for Redear Sunfish have declined over the last three surveys. Total CPUE of Redear Sunfish in 2019 (33.0/h) was lower than in 2017 (58.0/h) and 2015 (93.0/h; Figure 4). Redear Sunfish up to 9 inches in length (PSD-M = 5) were caught, which along with the presence of large Redbreast Sunfish and Bluegill, and excellent bank fishing access, makes this lake a desirable destination for sunfish anglers. The state record Redear Sunfish was caught from Lady Bird Reservoir in 1997 and weighed 2.99 pounds. Common Carp: Lady Bird Reservoir is renowned among carp anglers (in the United States and abroad) as one of the best trophy carp waters in the U.S. because of catches weighing greater than 40 pounds. Two carp tournaments at Lady Bird Reservoir in 2006 (ATC and Texas Carp Challenge) resulted in a direct expenditure of $101,000 (TPWD, unpublished data). Tournament prize money is not normally high but, the TCC tournament winner received $25,000 and the angler that broke the state record received $250,000. Common Carp electrofishing catch rate in 2019 was 4.0/h. By comparison, in 2015, the catch rate was 2.0/h and in 2011 it was 13.0/h (Figure 5; no length measurements were taken in 2019). In 2015, no carp above the maximum length (33 inches) were recorded, while in 2011 CPUE-33 was 1.0. Small carp (< 14 inches in length) were not present in any of the electrofishing and gill netting surveys between 2007 and 2019 (Farooqi and De Jesus 2016). Electrofishing is generally less effective for sampling Common Carp, but tournament data can provide valuable information. Although requested, due to unknown factors no data was made available from the ATC tournament between 2017 and 2019 and the tournament was not held in 2020. No surveys specifically targeting Common Carp were conducted during the survey period. Largemouth Bass: In 2019, the reservoir contained a low to moderate density Largemouth Bass population relative to bass populations in other central Texas reservoirs. The total catch rate of Largemouth Bass was 73.0/h in 2019 compared to catch rates of 81.6/h in 2017, and 171.0/h in 2015 (Figure 6). Electrofishing catch rate for Largemouth Bass 14 inches and longer (CPUE-14) was 26.0/h. This was similar to that obtained in 2017 (25.6/h), but was lower than in 2015 (56.0/h). The electrofishing CPUE of Largemouth Bass exceeding the upper end of the slot length limit (21 inches) had improved somewhat since 2015; CPUE-21 was 2.0/h in 2019 and 3.0/h in 2017 compared to 0.0/h in 2015 (Figure 6). Compared to the 2015 data, the population size structure from 2017 to 2019 was verging on being characteristic of a lower density Largemouth Bass population with larger individuals (Figure 6) based on expected ranges from Gabelhouse (1984) for PSD (50 -80), PSD-P (30-60), and PSD-M (10-25). Overall, body condition was good, as mean relative weights of most size classes of bass exceeded 90 (Figure 6). Although the minimum sample size requirement for a Category 2 age and growth evaluation (n=13) was not met in 2019 (n=6), the data that was collected reflects that of previous surveys (Farooqi and De Jesus 2016) which showed that on average, Largemouth Bass in Lady Bird Reservoir reached 14 inches between ages 2 and 3 (Figure 7), and this is about average compared to values for the Edwards Plateau ecological area (Prentice 1987). Genetic evaluation was not required in 2019. However, during the previous three evaluations Florida Largemouth Bass influence was relatively constant, ranging from
7 61.9% to 68.0% (Farooqi and De Jesus 2016). The reservoir was last stocked with Florida Largemouth Bass in 2016 and ShareLunker Largemouth Bass in 2014.
8
Fisheries Management Plan for Lady Bird Reservoir, Texas
Prepared – July 2020
ISSUE 1: The recent decline of vegetation in Lady Bird Reservoir has largely been due to a
reduction in the abundance of fanwort cause by scouring during flood events (Brent
Bellinger pers. com). Eurasian watermilfoil has not been recorded since 2015 and hydrilla
has never been established. Based on these findings, the frequency of aquatic vegetation
surveys can be reduced without compromising the integrity of monitoring efforts.
MANAGEMENT STRATEGIES
1. Conduct biennial aquatic vegetation surveys.
2. Continue collecting catch rate information on Grass Carp (escapees from Austin Reservoir) from
bycatch at the ATC Common Carp tournament by working with CAG to reduce non-reporting.
ISSUE 2: Bank fishing access at Lady Bird Reservoir is excellent and has been enhanced by
designated fishing areas on the newly constructed boardwalk. However, the safety
aspect of angling in close proximity to other users on the boardwalk has been raised,
prompting the COA to hold public meetings to discuss whether or not fishing should
continue on the boardwalk.
MANAGEMENT STRATEGY
1. Continue to work with the COA to provide input relative to safeguarding angling access on the
boardwalk. Add more habitat/fish attractors in the vicinity of the fishing areas of the boardwalk.
ISSUE 3: Catch-and-release fishing for Common Carp is a popular activity on this reservoir and the
annual ATC tournament attracts many out-of-state anglers. Data is needed to adequately
manage the fishery.
MANAGEMENT STRATEGY
1. Continue working with CAG to access future catch data from the ATC Common Carp tournament
and missing data from 2017-2019.
ISSUE 4: Many invasive species threaten aquatic habitats and organisms in Texas and can
adversely affect the state ecologically, environmentally, and economically. For example,
zebra mussels (Dreissena polymorpha) can multiply rapidly and attach themselves to any
available hard structure, restricting water flow in pipes, fouling swimming beaches and
plugging engine cooling systems. Giant salvinia (Salvinia molesta) and other invasive
vegetation species can form dense mats, interfering with recreational activities like
fishing, boating, skiing and swimming. The financial costs of controlling and/or eradicating
these types of invasive species are significant. Additionally, the potential for invasive
species to spread to other river drainages and reservoirs via watercraft and other means
is a serious threat to all public waters of the state.
MANAGEMENT STRATEGIES
1. Cooperate with the controlling authority to post appropriate signage at access points around the
reservoir.
2. If applicable, contact and educate marina owners about invasive species, and provide them with
posters, literature, etc. so that they can in turn educate their customers.
3. Educate the public about invasive species through the use of media and the internet.
4. Make a speaking point about invasive species when presenting to constituent and user groups.
5. Keep track of (i.e., map) existing and future inter-basin water transfers to facilitate potential9 invasive species responses.
10 Objective-Based Sampling Plan and Schedule (2020–2024) Sport fish, forage fish, and other important fishes Sport fishes in Lady Bird Reservoir include Largemouth Bass, Guadalupe Bass, Channel Catfish, Flathead Catfish, Crappie, White Bass, and Common Carp. Known important forage species include Bluegill, Redbreast Sunfish, Redear Sunfish, and Gizzard Shad. Underutilized or low-density fisheries Crappie: No trap netting has been conducted for crappie since 1999 (0.0/nn) because of historically low catch rates. A creel survey in 2002 did not capture directed effort for this species and no catches were documented. Sampling this population is not a priority for 2020-2024. Channel Catfish: Channel Catfish were stocked in Lady Bird Reservoir three times in the late 1960s, and in 2000 and 2001. Subsequent gill net surveys were unable to detect an increase in relative abundance. Channel Catfish accounted for 6.6% of the directed fishing effort in the last creel survey conducted on the reservoir (2002), but no catches were documented. The supplemental Channel Catfish stocking strategy was abandoned in 2004. Channel Catfish gill netting catch per unit effort (CPUE) in 2003, 2004, 2008, and 2012 were 0.6, 0.4, 1.0, and 0.4/nn respectively. Sampling this population is not a priority for 2020- 2024. Flathead Catfish: Flathead catfish are present in low abundance based on gill netting surveys. Flathead Catfish CPUE in 1999, 2003, 2008, and 2012 were 0.3, 0.4, 0.6, and 0.6/nn respectively. A creel survey in 2002 did not capture directed effort for this species and no catches were documented. Sampling this population is not a priority for 2020-2024. White Bass: White Bass are present in very low abundance based on gill netting surveys. None were caught in 1999, 2003, and 2011, and a CPUE of 0.2/nn was obtained in 2007. A creel survey in 2002 did not capture directed effort for this species and no catches were documented. Sampling this population is not a priority for 2020-2024. Guadalupe Bass: Catch per unit effort in 2003, 2007, and 2011 were 7.0, 2.0, and 0.0/h respectively. This species does not provide a significant fishery. Sampling this population is not a priority for 2020 – 2024. We will still monitor presence/absence with practical effort estimates from electrofishing surveys. Survey objectives, fisheries metrics, and sampling objectives Largemouth Bass: Largemouth Bass are the most popular sport fish in Lady Bird Reservoir. Largemouth Bass accounted for 66.7% of the directed fishing effort in the last creel survey (2002), and 5,264 were caught at a rate of 0.96/h. A ShareLunker weighing 13.0 lbs. was caught from Lady Bird Lake in 2014. A Largemouth Bass weighing 13.5 lbs. was captured in 2015, but it was not submitted to the ShareLunker program. The popularity and growing reputation for quality Largemouth Bass fishing at this reservoir in Austin warrant sampling time and effort. Largemouth Bass are managed with a 14- to 21-inch slot regulation. Electrofishing trend data on CPUE, size structure, and body condition since 2006 indicates a very stable population. Sampling every 4 years will provide adequate data to manage this fishery. A minimum of 12 randomly selected 5-min electrofishing sites will be sampled in 2023, but sampling will continue at random sites until 50 stock-size fish are collected and the RSE of CPUE-S is ≤ 25 (the anticipated effort to meet both sampling objectives is 12-15 stations with 80% confidence). Exclusive of the original 12 random stations, three additional random stations will be pre-determined in the event some extra sampling is necessary. If failure to achieve either objective has occurred after one night of sampling and objectives can be attained with 6-12 additional random stations, another night of effort will be expended. As time permits, schedule a creel survey to get the a more up to date status of the fishery.
11 Bluegill, Redbreast Sunfish, Redear Sunfish, and Gizzard Shad: Bluegill, Redbreast Sunfish, Redear Sunfish and Gizzard Shad are the primary forage at Lady Bird Reservoir. Like Largemouth Bass, trend data on CPUE and size structure of Bluegill, Redbreast Sunfish and Gizzard Shad have been collected biennially since 1996 and indicate that variations in abundance and population characteristics of forage species can be adequately monored by sampling every 4 years. Continuation of sampling, as per Largemouth Bass above, will allow for monitoring of large-scale changes in Bluegill, Redbreast Sunfish, and Gizzard Shad relative abundance and size structure. Sampling effort based on achieving sampling objectives for Largemouth Bass will result in sufficient numbers of Bluegill, Redbreast Sunfish, Redear Sunfish and Gizzard Shad for size structure estimation (PSD and IOV; 50 stock-size fish minimum at 5-12 stations with 80% confidence), but not for relative abundance estimates (RSE < 25 of CPUE-Total (CPUE-T); anticipated effort is 25-30 stations). At the sampling effort needed to achieve sampling objectives for Largemouth Bass, the expected RSE for CPUE-T is 30 for Bluegill, Redbreast Sunfish, Redear Sunfish, and 35 for Gizzard Shad. No additional effort will be expended to achieve an RSE=25 for CPUE of Bluegill, Redbreast Sunfish, and Gizzard Shad. Instead, Largemouth Bass body condition can provide information on forage abundance, vulnerability, or both relative to predator density. Relative weight of Largemouth Bass > 8” TL will be determined from their length/weight data (maximum of 10 randomly-selected fish weighed and measured per inch class). Common Carp Common Carp accounted for 9.4% of the directed fishing effort in the last creel survey (2002), and was the second most sought-after species at Lady Bird Lake (excluding the 13.5% of effort targeting “any species/no preference”). Basic monitoring of this fishery is warranted. However, electrofishing is ineffective at adequately sampling the carp population. Instead, data gathered from the annual ATC tournament at Lady Bird Reservoir, should provide larger sample sizes, and greater information on catch rates, size structure, and body condition. This is a total-weight competition i.e., all sizes of captured carp are included in the data. Since 2012, length and certified weights of individual Common Carp captured at the ATC have been provided by CAG except for 2017 to 2019. In 2020 the tournament was cancelled. The available data suggest that Lady Bird Reservoir has a low-density Common Carp population dominated by larger individuals. Continue working with CAG to access missing catch data from 2017 to 2019, and subsequent data from future ATC tournaments.
12
Literature Cited
Anderson, R. O., and R. M. Neumann. 1996. Length, weight, and associated structural indices. Pages
447-482 in B. R. Murphy and D. W. Willis, editors. Fisheries techniques, 2nd edition. American
Fisheries Society, Bethesda, Maryland.
Dibble, E. D., K. J. Killgore, and S. H. Harrel. 1996. Assessment of fish-plant interactions. American
Fisheries Society Symposium 16:357-372
DiCenzo, V. J., M. J. Maceina, and M. R. Stimert. 1996. Relations between reservoir trophic state and
Gizzard Shad population characteristics in Alabama reservoirs. North American Journal of Fisheries
Management 16:888-895.
Durocher, P. P., W. C. Provine, and J. E. Kraai. 1984. Relationship between abundance of Largemouth
Bass and submerged vegetation in Texas reservoirs. North American Journal of Fisheries
Management 4:84-88.
Farooqi, M. A. and M. J. De Jesus. 2016. Statewide freshwater fisheries monitoring and management
program survey report for Lady Bird Reservoir, 2015. Texas Parks and Wildlife Department, Federal
Aid Report F-221-M-3, Austin.
Gabelhouse, D. W. 1984. A length-categorization system to assess fish stocks. North American Journal of
Fisheries Management 4:273-285.
Guy, C. S., R. M. Neumann, D. W. Willis, and R. O. Anderson. 2007. Proportional size distribution
(PSD): a further refinement of population size structure index terminology. Fisheries 32(7):348.
Magnelia, S. J. and C. C. Bonds. 2004. Statewide freshwater fisheries monitoring and management
program survey report for Lady Bird Reservoir, 2003. Texas Parks and Wildlife Department, Federal
Aid Report F-30-R, Austin.
Magnelia, S. J. and M. J. De Jesus. 2008. Statewide freshwater fisheries monitoring and management
program survey report for Lady Bird Reservoir, 2007. Texas Parks and Wildlife Department, Federal
Aid Report F-30-R-31, Austin.
Prentice, J.A. 1987. Length-weight relationships and average growth rates of fishes in Texas. Texas
Parks and Wildlife Department, Inland Fisheries Division Management Data Series No. 6, Austin.
Texas Commission on Environmental Quality. 2020. Trophic classification of Texas reservoirs. 2020
Texas Integrated Report for Clean Water Act Sections 305(b) and 303(d), Austin. 15 pp.
Thompson, F. D. 1943. German Carp responsible for first state hatchery. Texas Game and Fish: 8-9,
14.13
Tables and Figures
Table 1. Characteristics of Lady Bird Reservoir, Texas.
Characteristic Description
Year constructed 1960
Controlling authority City of Austin
County Travis
Reservoir type Retired power cooling/recreational
Shoreline Development Index 4.1
Conductivity 492 µS/cm
Table 2. Boat ramp characteristics for Lady Bird Reservoir, Texas, October 2019. This is a stable-level
Reservoir (conservation level is 428 feet above mean sea level).
Latitude Parking Elevation at
Longitude capacity end of boat
Boat ramp (dd) Public (N) ramp (ft.) Condition
Festival Beach 30.248383 Y 8 N/A Good
-97.727817
I-35 near Holiday 30.251413 Y 12 N/A Good
Inn -97.73614014
Table 3. Harvest regulations for Lady Bird Reservoir, Texas.
Species Bag limit Length limit
Catfish: Channel Catfish, their hybrids 25 12-inch minimum
and subspecies (in any combination)
Catfish, Flathead 5 18-inch minimum
Carp, Common No limit 33-inch maximum*
Bass, Largemouth 5 14- to 21-inch slot**
Bass: Spotted, Guadalupe 5 No limit
(in any combination)
Crappie: White and Black Crappie, 25 10-inch minimum
their hybrids and subspecies (in any combination)
* Only one fish 33 inches or greater may be retained.
** Only one fish over 21 inches may be retained.15
Table 4. Stocking history for Lady Bird Lake, Texas. Life stages are fry (FRY), fingerlings (FGL),
advanced fingerlings (AFGL), adults (ADL) and unknown (UNK). Life stages for each species are defined
as having a mean length that falls within the given length range. For each year and life stage the species
mean total length (Mean TL; in) is given. For years where there were multiple stocking events for a
particular species and life stage the mean TL is an average for all stocking events combined.
Life Mean
Species Year Number Stage TL (in)
Atlantic Croaker 1975 250 2.0
Total 250
Channel Catfish 1966 400 UNK 0.0
1967 2,400 AFGL 7.9
1969 27,100 AFGL 7.9
2000 29,988 AFGL 4.9
2001 24,974 AFGL 10.1
2012 322 ADL 11.1
2018 126,027 FRY 0.8
Total 211,211
Coppernose Bluegill 1981 5,000 UNK 0.0
Total 5,000
Florida Largemouth Bass 1998 52,800 FGL 1.4
1998 108,660 FRY 0.3
2016 47,352 FGL 1.6
Total 208,812
Green Sunfish x Redear Sunfish 1966 300 0.0
1969 300 0.0
Total 600
Kemp's Largemouth Bass 1984 15,980 3.0
1987 6,300 1.0
1988 21,209 1.0
Total 43,489
Largemouth Bass 1966 94,350 UNK 0.0
1967 5,050 UNK 0.0
1973 8,000 UNK 0.0
Total 107,400
Northern Pike 1974 2,984 0.0
1975 3,389 0.0
1976 10,400 0.0
1981 23,003 0.0
Total 39,776
Palmetto Bass (Striped X White Bass hybrid) 1974 500 UNK 0.0
1975 20,000 UNK 0.0
1976 13,000 UNK 0.0
1977 9,994 UNK 0.0
1980 6,140 UNK 0.0
1983 10,450 UNK 0.016
Life Mean
Species Year Number Stage TL (in)
Palmetto Bass (cont.) 1984 11,900 FGL 2.0
1986 21,194 FGL 2.0
Total 93,178
Red Drum 1975 100 UNK 0.0
Total 100
Redear Sunfish 1981 2,000 0.0
Total 2,000
ShareLunker Largemouth Bass 2014 11,174 FGL 2.0
Total 11,174
Smallmouth Bass 1975 301 UNK 0.0
1978 15,000 UNK 0.0
Total 15,301
Spotted Bass 1974 14,400 0.0
Total 14,400
Striped Bass 1977 108,475 UNK 0.0
1978 340 UNK 0.0
1983 5,317 UNK 0.0
Total 114,132
Walleye 1974 2,500 FRY 0.2
1975 1,011,500 FRY 0.2
Total 1,014,00017
Table 1. Objective-based sampling plan components for Lady Bird Reservoir, Texas 2019–2020.
Gear/target species Survey objective Metrics Sampling objective
Electrofishing
Largemouth Bass Abundance CPUE – stock RSE – stock ≤ 25
Size structure PSD, length frequency N ≥ 50 stock
N = 13, 13.0 – 14.9
Age-and-growth Age at 14 inches
inches
Condition Wr 10 fish/inch group (max)
Redbreast Sunfish a Abundance CPUE – total RSE ≤ 25
Size structure PSD, length frequency N ≥ 50 stock
Bluegill a Abundance CPUE – total RSE ≤ 25
Size structure PSD, length frequency N ≥ 50 stock
Redear Sunfish a Abundance CPUE – total RSE ≤ 25
Size structure PSD, length frequency N ≥ 50 stock
Gizzard Shad a Abundance CPUE – total RSE ≤ 25
Size structure Length frequency N ≥ 50 stock
Prey availability IOV N ≥ 50 stock
Common Carp a Abundance CPUE – total RSE ≤ 25
Size structure PSD, length frequency N ≥ 50 stock
a No additional effort will be expended to achieve an RSE ≤ 25 for CPUE and N ≥ 50 stock of Redbreast
Sunfish, Bluegill, Redear Sunfish, Gizzard Shad, and Common Carp if not reached from designated
Largemouth Bass sampling effort. Instead, Largemouth Bass body condition can provide information on
sunfish and Gizzard Shad abundance, vulnerability, or both relative to predator density.18 Table 2. Survey of structural habitat types, Lady Bird Reservoir, Texas, 2019. Habitat type Estimate % of total Natural Shoreline 15.8 miles 86.7 Natural Shoreline/Piers/Docks 1.3 miles 7.2 Gravel Shoreline 0.1 miles 0.5 Rock Bluff 0.6 miles 3.2 Bulkhead/Piers/Docks 0.3 miles 1.5 Bulkhead 0.2 Miles 0.9 Table 7. Survey of aquatic vegetation, Lady Bird Reservoir, Texas, 2016 – 2019. Surface area (acres) is listed with percent of total reservoir surface area in parentheses. Vegetation 2016 2017 2018 2019 Native submersed 0.0 (0.0) 0.0 (0.0) 5.1 (1.1) 0.0 (0.0) Native floating-leaved 0.0 (0.0) 0.0 (0.0) 0.0 (0.0) 0.0 (0.0) Native emergent 2.9 (0.6) 1.0 (0.2) 2.9 (0.6) 4.0 (0.8) Non-native 0.0 (0.0) 0.0 (0.0) 0.0 (0.0) 0.0 (0.0)
19
Gizzard Shad
Figure 1. Number of Gizzard Shad caught per hour (CPUE) and population indices (RSE and N for
CPUE and SE for IOV are in parentheses) for fall electrofishing surveys, Lady Bird Reservoir, Texas,
2015, 2017 and 2019.20
Redbreast Sunfish
Figure 2. Number of Redbreast Sunfish caught per hour (CPUE) and population indices (RSE and N for
CPUE and SE for size structure are in parentheses) for fall electrofishing surveys, Lady Bird Reservoir,
Texas, 2015, 2017 and 2019.21
Bluegill
Figure 3. Number of Bluegill caught per hour (CPUE) and population indices (RSE and N for CPUE and
SE for size structure are in parentheses) for fall electrofishing surveys, Lady Bird Reservoir, Texas, 2015,
2017 and 2019.22
Redear Sunfish
Figure 4. Number of Redear Sunfish caught per hour (CPUE) and population indices (RSE and N for
CPUE and SE for size structure are in parentheses) for fall electrofishing surveys, Lady Bird Reservoir,
Texas, 2015, 2017 and 2019.23
Common Carp
Figure 5. Number of Common Carp caught per hour (CPUE) and population indices (RSE and N for
CPUE and SE for size structure are in parentheses) for electrofishing surveys, 2011 and 2015, Lady Bird
Reservoir, Texas. Vertical line represents the 33-inch maximum length limit introduced in 2009 (only one
fish ≥33 inches can be retained).24
Largemouth Bass
Figure 6. Number of Largemouth Bass caught per hour (CPUE, bars), mean relative weight (diamonds),
and population indices (RSE and N for CPUE and SE for size structure are in parentheses) for fall
electrofishing surveys, Lady Bird Reservoir, Texas, 2015, 2017 and 2019. Vertical lines represent slot
length limit at the time of sampling. The horizontal line represents optimum relative weight.25
Largemouth Bass
Figure 7. Length at age for Largemouth Bass (n=6) collected by electrofishing at Lady Bird Reservoir,
Texas, October 2019.26
Proposed Sampling Schedule
Table 8. Proposed sampling schedule for Lady Bird Reservoir, Texas. Survey period is June through
May. Electrofishing surveys are conducted in the fall or spring as indicated. Standard survey denoted by
S and additional survey denoted by A.
Survey year
2020-2021 2021-2022 2022-2023 2023-2024
Angler Access S
Structural Habitat S
Vegetation A S
Electrofishing – Fall S
Electrofishing – Spring
Electrofishing – Low frequency
Trap netting
Gill netting
Baited tandem hoop netting
Creel survey
Report S27
APPENDIX A – Map of sampling locations
Location of fall electrofishing sampling sites, Lady Bird Reservoir, Texas, 2019. This is a stable-level
reservoir (428 ft. above mean sea level).28
APPENDIX B – Map of structural habitat
Structural habitat survey map for Lady Bird Reservoir, Texas, August 2019.29
APPENDIX C – Map of vegetation survey
Aquatic vegetation survey coverage map for Lady Bird Reservoir, Texas, August 2019.30
APPENDIX D – Catch rate of all targeted species from all
gears
Number (N) and catch rate (CPUE; RSE in parentheses) of all target species collected from all gear types
from Lady Bird Reservoir, Texas, 2019. Sampling effort was 1 hour for electrofishing.
Electrofishing
Species
N CPUE
Gizzard Shad 50 50.0 (20)
Threadfin Shad 2 2.0 (100)
Longnose Dace 7 7.0 (100)
Common Carp 4 4.0 (56)
Redbreast Sunfish 217 217.0 (38)
Green Sunfish 1 1.0 (100)
Warmouth 2 2.0 (67)
Bluegill 58 58.0 (42)
Longear Sunfish 26 26.0 (48)
Redear Sunfish 33 33.0 (41)
Redspotted Sunfish 12 12.0 (46)
Largemouth Bass 73 73.0 (13)
Logperch 5 5.0 (69)
Rio Grande Cichlid 5 5.0 (55)
Triploid Grass Carp 1 1.0 (100)In accordance with Texas State Depository Law, this publication is available at the
Texas State Publications Clearinghouse and/or Texas Depository Libraries.
© Texas Parks and Wildlife, PWD RP T3200-1385 (08/20)
TPWD receives funds from the USFWS. TPWD prohibits discrimination on the basis of race, color, religion,
national origin, disability, age, and gender, pursuant to state and federal law. To request an accommodation or
obtain information in an alternative format, please contact TPWD on a Text Telephone (TTY) at (512) 389-8915
or by Relay Texas at 7-1-1 or (800) 735-2989 or by email at accessibility@tpwd.texas.gov. If you believe you
have been discriminated against by TPWD, please contact TPWD, 4200 Smith School Road, Austin, TX 78744,
or the U.S. Fish and Wildlife Service, Office for Diversity and Workforce Management, 5275 Leesburg Pike, Falls
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